P38 mapk inhibitor sb203580

Recombinant human TGF‐β protein was obtained from PeproTech (Rocky Hill, NJ, USA). Primary antibodies against GSK‐3β (27C10), GSK‐3β (Ser9), AKT (C67E7), p‐AKT (Ser473) were purchased from Cell Signaling Technology (Danvers, MA, USA). Primary antibody against SP1(G447) was obtained from Bioworld (Bioworld Technology, Minneapolis, MN, USA). Protein A/G sepharose and primary antibodies against ubiquitin (SC‐166553) and β‐actin (SC‐130300) were obtained from Santa Cruz Biotechnology (Santa Cruz, CA, USA). Phycoerythrin (PE)‐labelled antibody against ULBP1 and ULBP2 were obtained from R&D (San Diego, CA, USA). Horseradish peroxidase (HRP)‐conjugated secondary antibody, Alexa Fluor 488‐conjugated secondary antibody, 4′, 6‐diamidino‐2‐phenylindole (DAPI) and lipofectamine 2000 were purchased from Invitrogen (Carlsbad, CA, USA). Proteasome inhibitor MG132 was obtained from Sigma‐Aldrich (St Louis, MO, USA). PrimeScript RT reagent Kit and SYBR Premix Ex TaqTM were products of TaKaRa. E.Z.N.A HP Total RNA Kit was purchased from Omega Bio‐Tek (Doraville, GE, USA). Smart pool siRNA against human SP1 (siSP1), GSK‐3β (si‐GSK‐3β) and control (siNC) were purchased from RiboBio (Guangzhou, China). ERK inhibitor PD98059, p38 MAPK inhibitor SB203580, PI3K inhibitor LY294002 and TGF‐β type I receptor inhibitor SB431542 were obtained from Sigma‐Aldrich.